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vitiated "character of the blood as their predisposing cause, 

 as every animal does not run the same risk of attack, and 

 when attacked, the same risk of falling a victim to them. 



1.035. The proportion of water in blood should vary from 

 800 to 900 parts in 1000 parts. If the water is less in pro- 

 portion the blood owing to its thickness is sluggish in its 

 flow. A certain state of fluidity is also necessary to keep 

 those salts, e.g., phosphates of lime and magnesia, in a soluble 

 condition, which are required to be absorbed and assimilated 

 into the system. Salts must be in a soluble condition to be 

 absorbed and excreted by glands, and a deficiency of water 

 in blood results in such diseases as gravels of uric acid or 

 oxallate of lime in the kidney or bladder. 



1.036. Besides water, food supplies to the blood, fats, 

 starch and sugar, by which the fatty tissues of the body are 

 nourished and by which also materials for respiration and 

 production of heat are supplied. 



1.037. The solid portion of blood consists of white (leu- 

 cocytes) and red blood corpuscles. White blood corpuscles are 

 larger, irregular in shape, endowed with amoeboid movements ; 

 while the red corpuscles are smaller and devoid of the power 

 of movement. The white blood corpuscles have a special con- 

 nection with health. They attack any foreign substances, 

 such as bacteria, that may invade the blood and destroy them 

 by digesting them and ejecting the undigested residue into 

 the blood. Wherever a wound occurs the white corpuscles 

 rush into the breach, preserve the tissue from the attack 

 of injurious organisms, break up and remove the accumulated 

 red corpuscles and gradually help to fill up the breach. The 

 red corpuscles have also an important function to perform, as 

 it is by their means that oxygen is conveyed to the various 

 tissues, which burn up the excess of hydro-carbons and carbo- 

 hydrates, thus simultaneously keeping up animal heat and 

 getting rid to a large extent of useless substances. The 

 actual agent which conveys the oxygen is iron to which also 



